146 research outputs found
On the use of polynomial models in multiobjective directional direct search
FCT - Fundacao para a Ciencia e a Tecnologia PTDC/MAT-APL/28400/2017; UIDB/00297/2020.Polynomial interpolation or regression models are an important tool in Derivative-free Optimization, acting as surrogates of the real function. In this work, we propose the use of these models in the multiobjective framework of directional direct search, namely the one of Direct Multisearch. Previously evaluated points are used to build quadratic polynomial models, which are minimized in an attempt of generating nondominated points of the true function, defining a search step for the algorithm. Numerical results state the competitiveness of the proposed approach.authorsversionpublishe
Isolation and fatty acid profile of selected microalgae strains from the Red Sea for biofuel production
The isolation of lipid-rich autochthonous strains of microalgae is a crucial stage for the development of a microalgae-based biofuel production plant, as these microalgae already have the necessary adaptations to withstand competition, predation and the temperatures observed at each production site. This is particularly important in extreme climates such as in Saudi Arabia. Resorting to fluorescence activated cell sorting (FACS) we screened for and isolated several microalgal strains from samples collected from the Red Sea. Relying on the fluorescence of BODIPY 505/515 (4,4-difluoro-1,3,5,7-tetramethyl-4-bora-3a,4a-diazasindacene) and growth performance, four promising candidates were identified and the total lipid content and fatty acid profile was assessed for biofuels production. Selected isolates were classified as chlorophytes, belonging to three different genera: Picochlorum, Nannochloris and Desmochloris. The lipid contents were assessed microscopically by means of BODIPY 505/515-associated fluorescence to detect intracellular lipid bodies, which revealed several lipid drops in all selected strains. This result was confirmed by lipid gravimetric determination, which demonstrated that all strains under study presented inner cell lipid contents ranging from 20% to 25% of the biomass dry weight. Furthermore, the fatty acid methyl esters profile of all strains seems ideal for biodiesel production due to a low degree of polyunsaturated fatty acid methyl esters and high amount of palmitic and oleic acids.NPST Program of King Saud University [11-ENE1719-02]info:eu-repo/semantics/publishedVersio
Optimização / Investigação Operacional
Editor Convidado: Ana Luísa Custódio João Gouveia, Richard Z. Robinson e Rekha Thomas, "Representações mínimas de polítopos" Teresa Grilo, Fernando Lobo Pereira e Sílvio Gama, "Controlo óptimo de sistemas dinâmicos impulsionados por escoamentos de Couette" Marta Pascoal e Marisa Resende, "Informação imprecisa na forma de conjuntos aproximativos – aplicação à otimização em redes" Susana Fernandes, "Representação proporcional – um problema de otimização inteira
Searching for new sources of innovative products for the food industry within halophyte aromatic plants: In vitro antioxidant activity and phenolic and mineral contents of infusions and decoctions of Crithmum maritimum L.
Aromatic halophyte plants are an outstanding source of bioactive compounds and natural products with potential use in the food industry. This work reports the in vitro antioxidant activity, toxicity, poly phenolic profile and mineral contents of infusions and decoctions from stems, leaves and flowers of Crithmum maritimum L, an aromatic and edible maritime halophyte (sea fennel). Aspalathus linearis (Burm.f.) Dahlg. (rooibos) herbal tea was used as a reference. Sea fennel's tisanes, particularly from leaves, were rich in phenolic compounds and five of them (p-hydroxybenzoic and ferulic acids, epicatechin, pyrocatechol and 4-hydroxybenzaldehyde) were here described in C maritimum for the first time. Chlorogenic acid was the dominant phenolic determined. Na was the most abundant mineral in all tisanes followed by Ca and Mg in leaves' tisanes and K in flowers. Sea fennel's samples had a similar antioxidant activity than those from A. linearis, and had no significant toxicity towards four different mammalian cell lines. Altogether, our results suggest that sea fennel can be a source of products and/or molecules for the food industry with antioxidant properties and minerals in the form, for example, of innovative health-promoting herbal beverages.FCT Investigator Programme [IF/00049/2012
Halophyte plants as potential tool against toxicity of food contaminants
FCT - Portuguese Foundation for Science and Technology (PD/BD/135329/2017), under the Doctoral Programme “Agricultural Production Chains –from fork to farm” (PD/00122/2012)
and under the project UID/AGR/04033/2019; and by European Investment Funds by FEDER/COMPETE/POCI–Operational Competitiveness and Internationalization Programme, under Project POCI-01-0145-FEDER-006958. L. Custódio acknowledges FCT for the ID/Multi/04326/2019 project, and Scientific Employment Stimulus (CEECIND/00425/2017)info:eu-repo/semantics/publishedVersio
A new insight into the influence of habitat on the biochemical properties of three commercial sea cucumber species
This work makes a comparative evaluation of the biochemical profile of three sea commercial cucumber species (Holothuria mammata, H. polii and H. tubulosa) caught from different locations of the Mediterranean Sea (SE Spain). All species had high levels of moisture (from 73.6% in H. mammata to 81.2% in H. tubulosa), crude ash (from 9.61% in H. mammata to 14.7% in H. tubulosa) and protein (3.01% in H. tubulosa to 11.1% in H. mammata). They also had a low fat content, from 0.21% in H. tubulosa to 0.55% in H. mammata. Holothuria polii had intermediate values between the other two species, for all considered variables. All species had adequate protein/lipid ratios (H. mammata, 20:1; H. polii, 23:1; H. tubulosa, 14:1) and low lipid levels, enriched in omega-3 polyunsaturated fatty acids, especially arachidonic acid. The fatty acid profile suggests that H. polii is feeding on sediments more influenced by terrestrial inputs than the remaining species. Holothuria mammata and H. tubulosa are feeding on marine food sources mainly, but also with some terrestrial influence. The most abundant amino acids detected were alanine, arginine, glutamic acid, and glycine. All species had similar contents of essential amino acids (EAA) and ratios of EAA/non-essential amino acids. Holothuria tubulosa had a high content of toxic metals including Cr, Pb and Ni. This work highlights differences in compositional characteristics between different species of the same genus (Holothuria) from different locations.info:eu-repo/semantics/publishedVersio
Significações parentais e adesão em psicologia pediátrica
A adesão às recomendações e prescrições médicas é
um dos problemas centrais na medicina da actualidade.
No tratamento das doenças crónicas pediátricas este
problema reveste-se de uma importância acrescida. Pelo
seu impacto na saúde dos utentes e na eficácia e
controlo de custos dos serviços, a não-adesão tem sido
um importante campo de investigação e aplicação da
psicologia da saúde.
Neste trabalho as autoras apresentam uma síntese
da evolução dos modelos psicológicos sobre adesão
médica, e da conceptualização do papel do psicólogo
nestas diferentes abordagens. E, a partir de um estudo
sobre as significações de mães de crianças com doença
cardíaca congénita, propõem uma leitura desenvolvimentista
das mesmas, e algumas sugestões para a intervenção
do psicólogo de pediatria como intermediário
na comunicação médico-família-criança, e como
facilitador de uma adesão mais autónoma e continuada.ABSTRACT: Compliance with medical prescriptions and recommendations
is one of the main problems in nowadays
medicine. In the treatment of chronic pediatric illness
this problem is even more important. Because of its
impact on health and on cost control, the domain of
noncompliance is an important field of research and
intervention for health psychology.
In this paper, the authors present a summary of the
psychological models of medical compliance and of
the psychologist's role on each model. We review the
results of a study on the meanings expressed by mothers
of children with congenital heart disease. And
based on a developmental perspective of these meanings,
we suggest some guidelines for the pediatric
psychologist's intervention.info:eu-repo/semantics/publishedVersio
ANÁLISE ECONÔMICA DE SOLUÇÕES PARA REDUZIR O CONSUMO DE ÁGUA POTÁVEL – ESTUDO DE CASO DE UMA RESIDÊNCIA EM JOINVILLE – SC
O objetivo deste estudo foi analisar as soluções econômicas para reduzir o consumo de água potável em uma residência em Joinville/SC. A pesquisa foi desenvolvida em uma residência unifamiliar, que possuía principalmente equipamentos convencionais. Primeiramente, levantou-se o perfil de consumo, estimado a partir de planilhas que foram preenchidas pelos residentes. Depois realizou-se a análise da redução de consumo com a substituição dos equipamentos convencionais por economizadores. Foram utilizadas as reduções teóricas de arejadores, restritores de vazão e válvula de descarga com acabamento do tipo “Dual flush”. Estudou-se a viabilidade do aproveitamento da água pluvial. Por fim, optou-se por combinar as duas estratégias de redução de consumo de água potável (aparelhos economizadores e o sistema de água pluvial). Estimou-se uma redução no consumo de 21,0%, caso fossem utilizados os equipamentos economizadores, com um retorno financeiro de 52 meses. Para o aproveitamento de água pluvial, a redução no consumo de água potável seria de 29,6%, e um retorno financeiro maior do que 50 anos. Na combinação dos sistemas, a economia financeira seria apenas R$ 2,84 por mês. Concluiu-se que adotar os equipamentos economizadores no lugar dos convencionais é a melhor opção custo-benefício, porém, ambientalmente, a combinação dos cenários seria o ideal.
Oxytocin and mental health in college students
Mental health is the result of a combination of many factors and has a great influence on multiple aspects of the life of young adults. Some studies have found associations between oxytocin levels and quality of social relations and mental health disorders. The concern with students' mental health is increasing because most mental disorders peak during or slightly before college age. Of the mental disorders in these age groups, depression and anxiety disorders are the most frequent. Oxytocin and temperament have been emphasized as individual determinants with a biological basis. To our knowledge, there are no studies that relate oxytocin, oxytocin receptors, psychological disturbances, and temperament. We aimed to study the association between plasma oxytocin levels and two polymorphisms (SNPs), in gene receptor, mental health and temperament disturbances in university students.info:eu-repo/semantics/publishedVersio
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